Leakage of US Nuclear Secrets

Kalpana Chittaranjan, Researcher, IDSA


May 1999 brought sharply into focus all aspects of US-China relations due to what the US claimed was the errant bombing of the Chinese embassy in Yugoslavia—which the Chinese stated was deliberate—as a result of outdated intelligence information, and the release of a US House select committee report which concluded that the Chinese government had obtained secrets on seven of the US' most advanced thermonuclear weapons. Though the report by the Select Committee on US National Security and Military Commercial Concerns with the People's Republic of China, better known as the Cox Report, after Christopher Cox, Republican of California, who headed the bipartisan nine-member House Committee, was submitted on May 25, the issue of China's alleged spying on US nuclear secrets has been festering in the US media for the better part of this year.

Alleged Chinese Espionage

Suspicions Arise

It was as early as November 22, 1990, that the New York Times had published an article headlined, "Chinese Atom-Arms Spying in US Reported,"1 which began, "Chinese intelligence agents succeeded in stealing nuclear-weapons secrets from the government's Lawrence Livermore National Laboratory in the 1980s, and the Federal Bureau of Investigation later conducted a long espionage inquiry into the theft, American intelligence experts said today." The report went on to add that "data stolen from Livermore had been used by the Chinese to construct a nuclear device, identified in some published accounts as an experimental neutron bomb, which the Chinese detonated in September 1988." This explosive revelation did not lead to a public fall-out as the story was not picked up by major outlets—it faded away as there were no calls for congressional investigations or the firing of high-level officials.2 The story was brought into focus again when a lengthy front-page article in New York Times on March 6, 1999,3 described the genesis of the case, including the role of Notra Trulock, who was the then director of the US Department of Energy's (DOE) intelligence office and "the apparent decision by National Security Adviser Sandy Berger and his staff to downplay the charges and delay acting on them to avoid ruffling relations with China,"4 by piecing together details and interviews provided by Clinton Administration officials. According to the article, China has made a leap in the development of nuclear weapons by using the nuclear secrets stolen from a US government laboratory, the Los Alamos National Laboratory,5 35 miles outside Santa Fe, in New Mexico, in the miniaturisation of its bombs. So far, China's nuclear weapon designs had been a generation behind the USA's as it was unable to produce small warheads that could be launched from a single warhead at multiple targets—which could form the backbone of a modern nuclear force. China had built and tested such small bombs by the mid-1990s. This breakthrough was accelerated by the theft of US nuclear secrets from Los Alamos. The espionage was believed to have taken place in the mid-1980s but detected only in 1995 after three scientists at Los Alamos analysed three years' worth of data from Chinese nuclear test results and found similarities to its most advanced miniature warhead)—the W-88, which can be deployed atop intercontinental ballistic missiles (ICBMs)6 and is presently carried aboard US Trident II D-5 submarine-launched ballistic missiles. US intelligence had learned in 1995 that the Chinese had acquired schematic drawings for the light, miniaturised warhead, the W-88, seven years earlier. There was division among the intelligence analysts over whether China had stolen the plans. While some in the Central Intelligence Agency (CIA) argued that the Chinese scientists could have figured it out for themselves, all agreed that there might have been a leak and the most obvious potential source for this would be Los Alamos.7

Wen Ho Lee

A handful of ethnic-Chinese scientists became the focus of FBI agents and among them, Wen Ho Lee, a Taiwan-born, US citizen and US- educated engineer, 59-year-old computer scientist and nuclear physicist, who was hired at Los Alamos in 1978 and worked on a team developing the trigger for the W-88 warhead, became a target. The investigators also came to the conclusion that China was continuing to steal from the government's major nuclear weapons laboratories, which, after the end of the Cold War,8 had been increasingly opened to foreign visitors. In 1982, Lee had a telephonic conversation with the scientist suspected of stealing neutron bomb secrets from the Lawrence Livermore National Laboratory and discussed the ongoing federal investigation of that case. The FBI eavesdropped on the call but did not launch an investigation of Lee at this stage.9 In the early 1980s, Lee collaborated with the FBI, and was able to provide the bureau with "useful information" in at least one case. In 1983, Lee is alleged to have transferred nuclear bomb data from a classified computer system at Los Alamos to an unclassified network which was open to outsiders.10 According to experts in and out of government, federal experts feared that the secret computer codes that were downloaded into the non-secure computer were given to China and were the distillation of more than fifty years of research on how to perfect nuclear weapons. The experts stated that using the programmes, which calculate step-by-step how a bomb explodes, weapon designers could produce simulations of nuclear explosions realistic enough to check the feasibility of new designs before having to take the expensive step of testing weapons in actual blasts. While the codes are equations rooted in the laws of physics, which at the most basic level is taught in high schools and colleges, added layers could turn the codes into "informational gems," which spell out not only how nuclear weapons can be constructed, but also how they can be made smaller, lighter and more powerful."11 Dr Mathew McKinzie, a former Los Alamos researcher who is now with the Natural Resources Defence Council, which is a Washington-based nuclear-arms tracking group, said, "It's the distillation of 50 years of work, over 1,000 nuclear tests and thousands upon thousands of man-hours."12 Between 1984 and 1988, according to an article in the Wall Street Journal, Lee published six unclassified technical papers, which focussed on how high explosives can be detonated to create shock waves capable of compressing a sphere of metal. These studies are relevant for the understanding of the behaviour of the "trigger" of the thermonuclear weapon, the relatively small fission bomb used for the ignition of the much larger fusion reaction. Apparently, Lee was part of the team that designed the W-88 warhead, focussing on calculations relating to implosion of the primary.13 Lee twice requested and received permission to travel to China (1986 and 1988), to attend and speak at conferences which were related to the unclassified aspects of his work.14 The conference in 1986 was organised by Beijing's Institute for Applied Physics and Computational Mathematics, and Lee "presented a paper discussing 'detonation velocity' and the hydrodynamic effects of explosives."15 In June 1988, Lee presented a second paper "about voids in metal that could interfere with a fast-moving explosion." His lecture entitled, "Material Void Opening Computation Using Particle Method," was considered relevant for nuclear-weapons design and some of China's weapons team could have been in the audience. The FBI believes that in the question-and-answer session following the lecture, Lee may have, intentionally or inadvertently, revealed critical technical information about the W-88's design.16 Earlier, Lee's wife, Sylvia, who also worked in the same laboratory as her husband, i.e., as a secretary at Los Alamos, occasionally arranged tours for foreign dignitaries and in 1987, she became an informant for the FBI, providing information of visiting Chinese delegations. In 1995, Lee made the last of the known unauthorised transfers of classified computer files, containing millions of lines of secret computer code.17 In spring 1997, Lee, who was already under investigation as a suspected spy for China, was allowed to run a sensitive new nuclear weapons programme, according to some senior government officials. A post-doctoral researcher who was a Chinese citizen was hired to become Lee's research assistant. The decisions to appoint Lee to the new post in 1997 and to allow him to hire a Chinese assistant have underscored doubts about the procedures followed by laboratory officials and the FBI in the Los Alamos case.18 Wen Ho Lee was fired on March 8 from Los Alamos for alleged security violations and identifed by US officials as an espionage suspect, despite their inability to charge him as a spy.19 The Los Angeles lawyer for Lee, Mark Holscher, issued his first detailed denial of allegations that his client spied for China. The six-page written statement issued on May 6, 1999, stated that Lee has never handed over secret information to China and that Lee and his wife have helped the FBI in other counter-intelligence matters. "Dr Wen Ho Lee is a loyal American, and has always fully cooperated with the government's investigation," the statement said.20

US Intelligence Agencies on the Case

In June 1995, a Chinese official gave CIA analysts a document, which appeared to be a 1988 Chinese government document describing the country's nuclear weapons programme. A senior official said that the document specifically mentioned the W-88 and described some of the warhead's key design features. This document, coupled with the findings of Los Alamos nuclear weapons experts who had pored over data from the most recent Chinese underground nuclear tests and had detected similarities between the latest Chinese and US bomb designs was brought to the attention of DOE's intelligence officials, especially Norta Trulok, who later became the secret star witness brought before the select Congressional committee (Cox Report). Trulok and his team took their findings to the FBI in the latter part of 1995 and early part of 1996. A team of Energy Department and FBI officials then travelled to the country's three weapons laboratories and went over travel and work records of laboratory scientists who had access to the relevant technology. By February 1996, the team had narrowed its focus to five possible suspects, including Wen Ho Lee, who, according to one official, "stuck out like a sore thumb." Trulok travelled to the CIA headquarters in early 1996 and briefed the officials there on the evidence his team had gathered on the apparent Chinese theft of US nuclear designs.21 Energy Department officials decided to brief the White House in early 1996, and a group of senior officials, including Trulok, met Sanday Berger, the Clinton Administration's present National Security Adviser, who was then the Deputy National Security Adviser. He was told that China appeared to have acquired the W-88 and that a spy for China could still be at Los Alamos. As Berger himself stated in an interview, "I was first made aware of this in 1996."22

Though the FBI formally opened a criminal investigation into the theft of the W-88 design in June 1996, the inquiry made little progress over the rest of the year. In early 1997, Frederico Pena became the Energy Secretary and officials said that a counter-intellgence programme which had been previously approved was quietly placed on the backburner for more than a year. A classified report on the laboratories was issued by the FBI in April 1997, which recommended, among other things, reinstating background checks on visitors to Los Alamos and Sandia. This recommendation was ignored by the laboratories and the Energy Department for 17 months. Meanwhile, Trulock and other intelligence officials "began to see new evidence" that the Chinese had other, ongoing spy operations at Los Alamos. Trulok was granted an appointment, after a four month delay, with Pena who directed the former to Berger at the White House. A White House official said, "In July 1997 Sandy was briefed fully by the DOE on China's full access to nuclear weapons designs, a much broader pattern." Berger was told that there was evidence of several other Chinese espionage operations that were still under way inside the weapons laboratories, which increased the importance of the issue. President Bill Clinton was then briefed by Berger on what he had learned and was updated on this issue over the next few months. CIA Director George Tenet and FBI Director Louis Freeh reinforced Trulock's warnings and met with Pena to discuss the lax security at the nuclear laboratories. While Pena and his aides began to meet with White House officials to prepare a presidential order on laboratory security, the FBI assigned more agents to follow-up on W-88 investigations, and they were able to gather new evidence about Wen Ho Lee. Berger flew to Beijing in August 1997 to prepare for the upcoming October summit between Presidents Bill Clinton and Jiang Zemin. Samore, a senior National Security Council (NSC) aide in charge of proliferation issues was then assigned to assess the damge from the Los Alamos spy case. Samore received a briefing from Trulock in August, and he later asked the CIA's directorate of intelligence to get a second opinion on how China had developed its smaller nuclear warheads. While the analysts agreed that there had been a serious compromise of sensitive technology through espionage at the weapons laboratories, they were less conclusive about the extent of the damage. China's sudden advance in nuclear design could be due to the ingenuity of its scientists, apart from other causes, the CIA argued. Berger, relying on the CIA report, said in September 1997, that the picture was less conclusive than Trulock was arguing. The FBI inquiry was stalled. At a September 1997 meeting between the bureau and the Energy Department, Freeh concluded that the FBI did not have enough evidence to arrest Lee; since the crime was believed to have occurred more than a decade earlier the investigators did not have sufficient evidence to obtain a secret wiretap on the suspect, officials said. DOE officials were informed by Freeh there was no longer an investigative reason to allow Lee to remain in his sensitive position. In February 1998, Clinton signed an order mandating new measures which the NSC had begun to draft in late 1997 as a new counter-intelligence plan for the weapons laboratories. Ed Curran, a former FBI counter-intelligence agent, was named to run a more vigorous counter-intelligence office at Energy Department headquarters in April 1998. The House Intelligence Committee requested an update of the case in July. Key law makers began to learn about the extent of the Chinese "theft" of US nuclear secrets in the latter part of 1998, when the Cox Committee, investigating the transfers of sensitive US technology to China, heard from Trulok. Meanwhile, Bill Richardson became the new Secretary of Energy in autumn 1998 and after being briefed by Trulock, he quickly reinstated background checks on all foreign visitors. The FBI had recommended this move 17 months earlier. While more former FBI counter-intelligence experts were placed at the laboratories, Richardson also doubled the counter-intelligence budget. In December 1998, Rep. Norman Dicks, a Democrat from Washington who was the ranking minority member on the House Intelligence Committee and also a member of the Cox Committee told Richardson that he was growing impatient with the Administration's slow response to ongoing requests and its inaction on the Los Alamos spy case. His complaint prompted action from the Energy Department which gave Lee a polygraph (lie-detector) test in December. A second test was administered by the FBI in February 1999 and Lee's answers were found to be deceptive.23 Lee is alleged to have quickly deleted more than 1,000 computer files containing large amounts of secret data that he had moved to an unclassified system. In March 1999, Lee was interviewed by the FBI and he granted authorisation for investigators to search his office computer. A reconstruction of the files revealed that he had downloaded the "legacy codes" and accompanying data, which "jeopardizes" the US nuclear arsenal. In November 1998, counter-intelligence experts sent a 25-page report to senior national security officials which warned that China was focussed on the nuclear weapons and that the computer system at the laboratories was vulnerable.24 The FBI investigation intensified while the Cox Committee completed a 700-page secret report. The committee, after hearing from both the CIA and the Energy Department analysts, had taken Trulock's assessment seriously. At the request of the Cox Committee, the CIA and other agencies are conducting a new, more thorough damage assessment of the case.25

According to American intelligence assessments, China is close to deploying a nuclear missile with a warhead whose design draws on "stolen" American secrets. A long-range Chinese missile, known as the Dong Feng-31, is being equipped with a small nuclear warhead using designs from secret American technology. Officials believe that the missile is expected to be deployed within three or four years, which would give China its first warhead using secret American technology. With the DF-31, China will achieve its goal of building a modern nuclear arsenal that relies on mobility to evade attacks. It will be a truck-based mobile that can be moved, which would make it more difficult to detect and destroy. US intelligence assessments say the DF-31 will have a range of approximately 5,000 miles and is expected for deployment as early as the year 2002 or 2003. A 1996 Air Force intelligence report on the DF-31 stated, "The DF-31 ICBM will give China a major strike capability that will be difficult to counter attack at any stage of its operation." It went on to add, "It will be a significant threat not only to US forces deployed in the Pacific theater, but to portions of the continental United States and to many of our allies."26 An earlier report stated that secrets that China "stole" in 1997 about a space radar that can expose submerged submarines could help in locating submarines from commercial satellites or airplanes, and might also help its own undersea weapons, intelligence experts said. Federal officials said that an American scientist gave radar secrets to China in 1997. While the implications are unclear, the experts say that at worst, American submarines are now in danger of losing some of their cover and among the most vulnerable are missile submarines, the most important part of the USA's nuclear arsenal, because of their stealthiness.27

Cox Report28

President Clinton agreed that national security had to be improved after the release of the Cox Report on May 25, 1999, which describes a pattern of systematic and successful Chinese espionage to learn American nuclear secrets. The panel, which consisted of five Republicans and four Democrats had carried out a year-long investigation. When the Committee began its inquiry, it looked at a narrow subject: what China was learning from American companies that used Chinese rockets to launch satellites. However, midway through its inquiry, the committee turned to the reports of nuclear espionage. The committee interviewed 150 witnesses and reviewed 500,000 pages of documents. While 30 per cent of the report remains classifed, the version made public often used words like "may" "could", or "possibly". Cox stated in an interview," An unfortunate byproduct of the rewriting process is that apparent speculation and opinion enters the report whereas in our final, classified report there were only facts."29 The core of the report presents two intertwined tales—China's "insatiable" appetite for American military technology; and Washington's laxity over sensitive exports and security at weapons laboratories. The three-volume report concludes that China has stolen design secrets for all seven nuclear warheads currently deployed on American missiles, which has enabled it to leap years ahead and modernise its nuclear weapons. The report says that "systematic" Chinese nuclear espionage began 20 years ago and almost certainly continues, but that this has not altered the military balance between Washington and Beijing because China still has few nuclear missiles. However, the committee warned that China is exploiting "stolen" secrets to develop a modern and more mobile nuclear capability that could pose a threat to American troops and allies in Asia and the Pacific. The report criticises the practices of two US satellite companies, Hughes Space and Communications International Inc. and Loral Space and Communications Ltd., for, at times, subordinating national security to the "bottom line". The report offers a new view of efforts by the Chinese military to funnel money to a Democratic fund raiser in 1996, i.e., that the money given by a Chinese military official, Lieut Col. Liu Chaoying, who met President Clinton at a 1996 benefit, "was an attempt to better her position in the United States to acquire computer, missile and satellite technologies." The report criticises the looser controls on technology exports, a cornerstone of President Clinton's commercial diplomacy. It does not, however, assign blame for lax security at the laboratories. A principal finding is that the USA did not become "fully aware of the magnitude of the problem" until 1995. Washington's policy of allowing corporations to police their own technology sales, a significant step taken in the first Clinton Administration, the report says, has not worked because national security interest "simply may not be related to improving a corporation's 'bottom line'." The committee found that where the subject of aid by US satellite manufacturers for Chinese scientists is concerned, in 1993, 1995 and 1996, the companies "transferred missile design information and know-how" to China "without obtaining the legally required licenses." This "illegally transmitted" information has improved the reliability of China's civilian and military rockets and "is useful for the design and improved reliability" of future Chinese ballistic missiles. It was former US President Ronald Reagan who had first approved the launch of American commercial satellites on Chinese rockets in 1988. The committee reported that his decision was based on two outdated factors:" insufficient domestic launch options in the aftermath of the Challenger disaster" and the belief that China "was a strategic balance against the Soviet Union in the context of the Cold War." The report, as a result, calls for strengthening American rocket-launching capabilities, improving the monitoring at foreign launch sites and tightening federal scrutiny of commercial space insurers and satellite exports. The report also warns that it had noted the lack of procedures to detect or prevent the movement of classified nuclear weapons information to less secure computer systems at the weapons laboratories.

Among the report's findings:30

l The Chinese government has 3,000 "front" companies in the United States, but American agencies seem to have little knowledge about their existence or activities. In the 1990s, China stepped up its use of front companies for espionage.

l China stole unspecified thermonuclear weapons information, possibly from a national weapons laboratory, in the mid-1990s. This is in addition to China's acquisition of design secrets on seven nuclear warheads, including the neutron bomb and the W-88, the most advanced, miniaturised warhead.

l China has stolen information relating to American re-entry vehicles, which shield warheads as they return to earth.

l China illegally obtained ballistic-missile guidance technology that it has exploited for its own weapons.

l China illegally obtained American research on electromagnetic weapons technology related to satellites in the late 1990s.

l China's agreement to allow monitoring of its use of American exports, which was announced at summit talks in Beijing in 1998 is "wholly inadequate" in general and "useless" in the case of advanced computers.

Response/Follow-Up to Cox Report

The White House response to the Cox Report was to acknowledge that a serious security breach existed while trying to assure Congress and the public that the Clinton Administration was working hard to improve security. Speaking at an unrelated domestic policy event in Texas, President Clinton stated, "First, let me say that I am particularly appreciative of the careful and bipartisan manner in which the committee did its work...Like many other countries, China seeks to acquire our sensitive information and technology. We have a solemn obligation to protect such national security information, and we have to do more to do it"31 Bill Richardson, the secretary of energy, said at a Press conference on May 25, "This Administration has acted on the problem; previous Administrations didn't act." He added, "Now, this is not a partisan issue; this is a bipartisan problem that we are trying to fix." Calling the Cox Report "an important, valuable, piece of work," he noted that he had begun moving aggressively to improve security and counter-espionage surveillance at the national weapons laboratories long before the report was released. He stated, "We have undertaken a total overhaul of the Department of Energy counterintelligence programme...We are fixing the problem. I can assure the American people that their nuclear secrets are now safe at the labs."32

China, expectedly, reacted harshly to the report. The Chinese government stated that the release of the Cox Report was meant to "disturb and destroy" Sino-American relations and to deflect attention from the US bombing of China's embassy in Belgrade. Zhu Bangzao, the Chinese Foreign Ministry spokesman, said that the panel led by Cox was "clinging to the Cold War mentality" and had produced a rumour-mongering report intended to advance "the theory of a China threat." Zhu repeated the government's long-standing denial that it stole any US nuclear technology.33 China's official Press attacked the credibility of the report by asserting that "the specter of McCarthyism looms large in the Cox Report." A commentary issued by the New China Agency on May 27 stated that the report provided "no legally tenable evidence" to back up its accusations that China has stolen advanced nuclear and missile technologies and used them in its own weapons programmes. The Cox Report uses "many vague terms such as 'may' and 'likely' to back up its accusations", the commentary added.34

The Senate approved measures on May 27 to expand overseeing of technology exports and to tighten security at weapons laboratories. The package would expand the role of intelligence agencies in reviewing export licences, boost Pentagon monitoring of satellite launches in China and require the Administration to report to Congress on any security breaches. It would also put the FBI solely in charge of all background investigations of workers at Energy Department weapons laboratories.35

Janet Reno, the US attorney general, faulted Justice Department and FBI subordinates for not coming to her in 1997 with their disagreement over whether to wiretap Wen Ho Lee. She was reacting to calls for her resignation.36 Earlier, National Security Adviser Sandy Berger also refused to heed calls for his resignation.

Notra Trulock, the Energy Department intelligence official who first raised the alarm about China's "theft" of American nuclear secrets recieved $10,000 and the Energy Department's Special Act Award from Bill Richardson on May 28.37 Richardson announced on May 30 that he would dismiss some department officials for failing to act on signs that China was "stealing"secrets from Los Alamos.38

China's State Council, or Cabinet organised a demonstration on May 31 at Beijing when professional surfer Fang Nan sat before his Chinese government-issue computer and began downloading sophisticated technical details about advanced US nuclear warheads. Zhao Quzheng, spokesman for the State Council, told Chinese and foreign reporters that the information China was accused of stealing—including critical design information on the W-88 warhead and six others—has long been openly available in the United Sates. He cited in particular the Nuclear Weapons Databook series published by the Natural Resources Defence Council. Quzheng noted, "Moreoever, in recent years, performance data about various types of nuclear warheads, ranging from the early MK-1 [the type of weapons used against Hiroshima in 1945] to the latest W-88, can easily be found on the Internet...They are no longer secrets, so there is nothing to steal." Fang went on to log on to the Internet and went to the Web page of the Federation of American Scientists, a Washington-based group concerned with weapons proliferation and other issues. The federation was founded by scientists who worked on the Mahattan Project and disseminates detailed information on nuclear weapons to encourage public debate on disarmament. The result of Fang's efforts, including a list of every US nuclear explosive weapon and its specification, were projected on a large screen. He then searched for W-88. The result—explosive yield, weight, length and diameter of the warhead, as well as a description of the specific materials used and its key design features, were described. Fang said he and several other Internet buffs thought of searching for nuclear information on the Internet after reading the Cox Report. They also found academic bulletin boards used by American scientists to be great sources of detailed information on US nuclear weapons, he said.39


At current levels, China's nuclear arsenal, by necessity and design, is modest when compared to that of the USA. Though the threat it poses to the USA is small, it is real. Out of its nearly 400 warheads, only about 20 are capable of reaching the USA while the latter has 8,300 operational warheads, nearly all of which could be targetted against China. China's long-range ballistic missiles carry a single warhead, are liquid-fuelled and number fewer than two dozen, while the USA has 982 ballistic missiles (including 432 aboard invulnerable Trident submarines), all of which carry multiple warheads (MIRVs) and are solid-fuelled, and thus can be launched at short notice.40

The obvious question, "In what way will the Chinese translate the knowledge gained from the alleged espionage on US nuclear weapons to weapons that are on par with the US," is best answered by The Washington Post's Vernon Lobe's online discussion on the state of US intelligence and national security on June 2, 1999. Loeb answered, "The answer is, no one knows. The Cox Committee seems to believe that the Chinese have actually used stolen US design secrets in the design of their next generation warheads. The US intelligence community isn't so sure. Top US weapons scientists say it isn't possible to actually design and build a warhead using the information the Chinese have obtained from the US, either from open sources or espionage."41



1. Stephen I. Schwartz, "A Very Convenient Scandal," The Bulletin of Atomic Scientists, May/June 1999, vol. 55, no.4.

2. Ibid.

3. James Risen and Jeff Gerth, "China Stole Nuclear Secrets From Los Alamos, US Officials Say," The New York Times, March 6, 1999.

4. n. 1.

5. "The Gadget", "Little Boy" and "Fat Man" (the latter two used for destroying the Japanese cities of Hiroshima and Nagasaki on August 6 and 9, respectively) were the world's first nuclear bombs that were designed and built at Los Alamos National Laboratory which continues to make bombs.

6. n. 3.

7. Daniel Klaidman and Milinda Liu, "Open Secrets," Newsweek, vol. CXXXIII, no. 12, March 22, 1999, p. 16.

8. Over the past two decades, the USA's nuclear weapons laboratories granted access to at least 36, 000 foreign scientists and researchers, broadly waiving security checks into their background even though a third of them came from so-called "sensitive countries" like China. Jonathan Broder, "US Grants Liberal Access to Labs," downloaded from URL on 25-5-1999.

9. The New York Times, May 2, 1999.

10. Ibid.

11. William J. Broad, "Unsecure Codes are Recipes for A-Bombs, Experts say", The New York Times, April 29, 1999.

12. Ibid.

13. n. 1.

14. The unclassified aspects of his work are relevant to a broad number of scientific and industrial aspects.

15. n. 1.

16. Ibid. While senior law enforcement and intelligence officials are not confident that Lee either passed on critical secrets to the Chinese and/or whether espionage was involved at all, the Chinese, while confirming Lee's attendance at the two scientific conferences, have vehemently denied the charges of spying. According to them, Lee had visited Beijing for a symposium on hydromechanics in 1986 and had presented an open lecture that had "nothing to do with 'secrets,'" and in 1988, Lee had joined 200 other scholars from different parts of the world at a physics conference which was co-sponsored by Pennsylvania's Drexel University, the US National Science Foundation, and China's Applied Physics and Computation Mathematics Institute, where, "his report covered general basic research and did not involve any confidential information." See Michael Laris, "China Says US Scientist Visited, but Told No Secrets," The Washington Post, March 23, 1999.

17. n. 9.

18. n. 3.

19. Vernon Loeb and Walter Pincus, "Prosecuting Lee is Problematic," The Washington Post, May 24, 1999.

20. James Risen, "Lawyer Issues Denial for Los Alamos Scientist Suspected of Spying for Beijing," The New York Times, May 8, 1999.

21. n. 3.

22. Ibid.

24. n. 9.

25. n. 3.

26. James Risen and Jeff Gerth, "China is Installing a Warhead Said to be Based on US Secrets," The New York Times, May 14, 1999.

27. William J. Broad, "US Loses Hold on Submarine-Exposing Radar Technique," The New York Times, May 11, 1999.

28. Some of the websites from which the Cox Report can be downloaded are: <http://www.cnn.com/ALLPOLITICS/resources/1999/Cox.report/>; <http://www.Washingtonpost.com/wp-srv/politics/daily/May 99/Coxreport.htm>.

29. Jeff Gerth and James Risen, "Spying Charges Against Beijing are Spelled Out by House Panel," The New York Times, May 26, 1999.

30. Ibid.

31. John M. Broder, "President's Sober Response Assures Public of Security Measures," The New York Times, May 26, 1999.

32. Ibid.

33. Michael Laris, "China Has Harsh Words For Report," The Washington Post, May 26, 1999.

34. Erik Eckhlom, "Chinese Press in Full Attack on Cox Report," The New York Times, May 28, 1999.

35. Tom Raum, "Senate Tightens Up on Tech Exports," The New York Times, May 27, 1999.

36. Michael J. Sniffen, "Reno Knocks Aides on China Wiretap," The Washington Post, May 28, 1999.

37. James Risen, "Energy Aides in Spying Case to be Honoured," The New York Times, May 28, 1999.

38. The New York Times, May 31, 1999.

39. Michael Laris, "Chinese Surfer Downloads US Nuclear Data," The Washington Post, June 1, 1999.

40. n. 1.

41. See transcript of Vernon Loeb's online discussion on "US Intelligence and National Security, " The Washington Post, June 2, 1999.